Not sure about yeast infections, but have had some bouts with some kind of crotch rot from time to time...hazard of my career path. I had a particularly bad version following prostrate cancer surgery (probably set in motion by a leaking catheder and poor cleanliness) that was put in it's place by prescription. I do not remember if there was an oral prescription at the time, but I've tried to keep some of the cream on hand just in case...also prescription---triamcinolone acetonide 0.5% cream. Ask your medical person about that.